Call No Man Masterby Joyce Collin-Smith This is an amazing book by Rodney Collin’ sister-in-law about her experiences on the spiritual
path with Rodney Collin and others.The Harmonious Circle: The Lives and Work of G.I. Gurdjieff, P.D. Ouspensky and their Followers

by James Webb
It is very helpful to put Gurdjieff, Ouspensky, Dr. Nicoll, etc.
into an historical
perspective and to begin to understand how Gurdjieff and
Ouspensky practiced the work and
how those practices are different from the "work" that is
practiced in Sharon's "school."Taking with the Left Handby William Patrick Patterson

Some of the early history about Alex Horn and others.

Rogue Messiahs: Tales of Self-Proclaimed Saviors by Colin Wilson

Madame Blavatsky and others.

Boyhood with Gurdjieff by Fritz Peters

First hand account of life with Mr. Gurdjieff at Fountainbleu

My Father's Guruby Jeffrey Mousaieff Masson

An account of growing up with Paul Brunton
(another "guru").

The Sociopath Next Doorby Martha Stout

Gurdjieff by Louis Pauwels

Morning of the Magicians by Jacques Bergier and Louis Pauwels

Mistakes Were Made (but not by me), Why We Justify Foolish Beliefs, Bad Decisions and Hurtful Acts by Carol Tavris and Elliot AronsonTales for the Son of My
Unborn Childby Thomas Farber
Stories about Berkeley, California in the 1960's.
There is an excellent chapter about the author's encounter
with Alex Horn and his "school."

People only see what they are prepared to see. Ralph Waldo Emerson

Did you ever wonder why only certain books were permitted to be read in school? Having to ask permission to read a certain book is called censorship. Are you not capable of making up your own mind about what to read and what to believe? Were you told never to read first hand accounts by Gurdjieff's and Ouspensky's students because your teachers were afraid you would find out how differently other Teachers treated their students?